The unexpected conundrum of endometrioid carcinoma in deep rectal endometriosis arising 11 years after total hysterectomy bilateral salpingo-oophorectomy

Dear Editor:Endometriosis largely affects women, particularly during the fertile age, causing dysmenorrhea, dyspareunia, chronic pelvic pain, and infertility in about 30 % of patients [1]. Its occurrence is estimated to be about 10 % in women in reproductive age, while postmenopausal endometriosis is much less frequent, affecting up to 2-4 % of women, usually in patients with a history of premenopausal disease.Pelvic deep endometriosis infiltrating the rectum and surrounding tissues usually causes severe symptoms, especially pain and obstruction, and its treatment is challenging, because of risk of injury of the pelvic organs and because of the high recurrence rate. Furthermore, even if endometriosis is a benign condition, it has the potential for malignant transformation [2], which occurs in 0.7-1 %, particularly in the ovaries [3].The endometrial heterotopic tissue is functionally capable of responding to exogenous, endogenous, or local hormonal stimuli, and this estrogen dependence ...